Preheat oven to 400°F (200°C). Toss beets and 1 tbsp (15 mL) oil. Seal in double-layer of foil. Roast 40 to 45 min. until beets are tender. Wearing oven mitts to avoid steam, open packet to cool. When beets are cool enough to handle, gently rub skins off using a paper towel. Cut beets into quarters.
In food processor, pulse beets with remaining 3 tbsp (45 mL) oil, half the Parmesan cheese, walnuts, lemon zest, lemon juice, garlic, salt and pepper until finely chopped.
Meanwhile, cook pasta according to package directions; reserving 1/4 cup (60 mL) cooking water. Drain pasta and toss with beet pesto and reserved cooking water. Serve sprinkled with remaining cheese, parsley or chives.
Roast a few more beets when you make this recipe. They're handy to have on hand to add to side dishes, salads and sandwiches.